This invention relates generally to catheters adapted to be inserted into the cardiovascular system of a living body and, more particularly, to an improved catheter having an improved distal end portion for more precise location in the particular artery of the cardiovascular system.
Catheters are often used in the performance of medical procedures such as coronary angiography for injecting dye, or the like, into the cardiovascular system for diagnosis; and angioplasty to widen the lumen of a coronary artery which has become at least partially blocked by a stenotic lesion causing an abnormal narrowing of the artery due to injury or disease. In these techniques the distal end of the catheter is introduced into the aorta by way of the femoral artery. The proximal end of the catheter is then manipulated so its distal end is inserted into the lumen of a selected coronary artery branching off from the aorta. A typical angioplasty procedure would involve initially inserting a guiding catheter into the cardiovascular system in the above manner, followed by a dilating catheter, a laser catheter, an atherectomy catheter, or the like, which is guided through the guiding catheter until its distal end portion is positioned within the stenotic lesion in the coronary artery to reduce the blockage in the artery. A diagnostic catheter would be used in the same manner.
The most common catheter used in treatment of the left coronary artery is what is often referred to as a "Judkins" catheter which has a specially shaped distal end portion for facilitating insertion into the artery. However, as will be specifically discussed, there are some disadvantages to the "Judkins" catheter, including its inability to align perfectly coaxially with selected artery and thus permit optimum treatment, and its inability to adequately support other devices such as balloon catheters. Also, the Judkins catheter forms relatively large angles when inserted into the cardiovascular system thus dissipating some of the axial forces transmitted through the catheter during use.